It is common practice to make all kinds of components and products from “plastics” using a variety of high-rate low-cost molding (injection, blow-molding and the like.) technologies. These objects can be fabricated at low labor costs but can have high dimensional tolerance, finish and the like. Examples range from all sorts of toys (GI Joe and Barbie Dolls) through all sorts of appliances, household goods, furniture and the like. The big advantage of plastic is that it can be manufactured at exceedingly low costs and has ubiquitous application when structural integrity is not required. The big disadvantage of monolithic thermoplastics is that they have low strength and stiffness and cannot be used for load-bearing structural applications. Advanced composites overcome this shortcoming by laminating reinforcing fibers into a polymeric matrix. There are three major disadvantages with advanced composites. First, the lamination process is highly labor intensive, not well suited to automation and results in components that are more expensive to produce that their metal equivalents. Second, reinforcement is achieved in essentially only two dimensions. Finally, high dimensional tolerance is hard to achieve and maintain leading to substantial fit-up, shimming and the like and high assembly (bonding and joining) costs. There is a clear and compelling need to develop technology that can produce structural components with high dimensional tolerance and finish at low manufacturing costs.
The above problems are well known and can be summarized as high manufacturing costs, mostly labor, not amenable to automation and the material is often sticky and disorderly in the lay-up stage. Also the mechanical fit-up for joining parts can be difficult and expensive. That is, it is estimated that 60% of manufacturing costs are incurred in joining components for major assemblies and subassemblies.
Thus, there is need and market for technology to produce large polymer articles of high strength in 3 dimensions, with good dimensional tolerance, so as to overcome the above prior art shortcomings.
There has now been discovered a method to make the above components and structures of polymeric material and yet be of surpassing strength in 3 dimensions.